1. Field of the Invention
The present invention relates to an authentication method, authentication system, payment system, user apparatus and recording medium containing a program for conducting authentication so as to facilitate a variety of commercial transactions.
2. Description of Related Art
In face-to-face transactions, if the purchaser has cash then the transaction will usually be settled in cash and, if not, then most often the purchase is consummated by credit card. Credit cards operate such that a signature alone enables the cardholder to make purchases up to within a certain limit from participating or member stores.
Credit cards are so handy (insofar as they eliminate the need to carry cash) that modern society is sometimes referred to as a cashless society or a credit-card society.
Moreover, with the recent rapid spread of the internet and other such communications networks it has now become possible to do on-line shopping over the internet. In this case, payment is by means of transmission of a member ID or password.
However, various security issues and disadvantages attend face-to-face transactions settled by credit card and the like, including authentication of participating member stores and card number skimming. Additionally, as far as the participating store is concerned, it is difficult to determine with certainty the true identity of the cardholder.
Additionally, in the case of online shopping and the like, there is the possibility that sensitive information, such as member ID numbers and passwords (which typically must be transmitted over the internet in order to complete the transaction) will be intercepted en route and put to unauthorized use, that is, used to make fraudulent purchases.